Lock nut



E. A. KWARNSTROM.

LOCK NUT.

APPLICATION FILED APR.28, 1920.

1,405,1 38, Patented Jan. 31, 1922.

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too ir r ur.

ToQaZZ whom it canoe 1th: 4

Beit known that 1, ,ER ig'A. .KwARN- srno'ir, ,a citizen of the United States, residing at Chicago, in the county: of Cook and State of Illinois, have invented certain new and useful Improvements in Look Nuts, of

whichthe following is a specification.

7 My invention .relatesgtoan improvement in loclrnuts and hasipartijcularreferenceto a device wherein a threaded wedge member is adapted tolie within av longitudinally extending recess formedin the nut in such a manner that a-wedging action :will' take place between the nut and thethreadedtpor tion of the ,boltupon which .the nut is car ried. gThe wedge member isfadapted to move withthe nut until one of its ends which projects beyond the nut comes in contact with the member orplate against which the nut is turned whereupon the threads ofthe wedge member will exerta sidewise thrust upon-the threads .of the bolt, and will bite intothe threads of the bolt,distorting them sufficiently to avoid being turned t-easily,.-and

atlthe sametime the wedge member-is forced inwardly towards the bottoms ofthe threads 2 of the bolt so that the nut isT held securely in osition on the bolt. without being t battered or without destruction of the threads to such an extent that the nut cannot be backed .ofi' t-hebo lt;without the use ofa wrench.

It is well known that nuts become loosened upon bolts because of vibration and that the constant pressure dueto the elasticity of the I metal. when a nut screwed down tightly on a bolt is the normal means relied upon for holding a nut 'inr'positio-n upon abolt and'that due to vibration there is a slight instant of time when the nut is out of contact with the metal and is, in effect,

floating and at this particular instant the nut moves a very slight amount and with each succeeding vibration continues this slight movement until it becomes loosened.

In my improved lock nut, due to the wedge action which I obtain between the bolt and the nut, and the surface against which the wedge contacts, I am able to so lock and wedge the nut and thebolt together that any vibration, however slight, will be taken up by the wedge member and the nut will therefore not be carried freely, even for a slight instant, and, therefore, there is not the liability of a nut becoming loosened through vibration. r

r 4 This 5. and other. 0

Another and iiurther ob-ject oii my inven; tion is thejprovision of a jd'eviceWhich-;is. T s mp ean l e f ci t n ope a ionaand which 1 is easy to insert and can" ibe,manufaltured in large. quantitiesF cheaply;

Specification of Letters'fPatentg Jan; I

bjects invention will be more fully and better. understood 5 i by reference to, the accompanying; :sheet' of drawingsgin which; i i

Figu l sview. 1n ;,elevatio of proved mventlon;

-Figure2 is' 'a view 1 my improved locknut; ,2 v, y Flgllre 3 i ma view 0112111116,3f33-g0f Figurefl I t ,7

. li igure ens a view ;.fin elevation of the threaded side? of my improved wedgemem-Q Figure 5 is aside viewof the sameinm' b rgzand- ,Referringi riow specifically ings, and in whichQlike reference characters refer to likes-parts throughout, a threaded o Figurefi is an-end viewoft-hevwedgemom;

bolt w 10 ,isshown vhaving the usual head; the 2 5;,

said bolt extending through; a'member 12.

A threaded nut--13- ;is I provided, the saidy'nut having a transverse, '1 recess; ,14; extending therethrough and; within -.=whic h a ithreajded wedge member 15isinserted; "J'Thfi outside wall 16 of the recess 14 isinclined so that I as the wedge member 16 is moved trans-"f versely, as hereinafter described, the said '90 member. will be driven inwardly towards the bottoms of the threads uponthe bolt 10 .{an-d willthus'bite into thethreads and se-- curely hold the nut 13, in position. The member 15 is threaded in the same manner as the nut 13, and projectsdownwardly a slightidistancebelow the edge-of the nut- 13 so'tha-t as the nut 13 'is turned, downe wardly on the bolt the member 15 will come oo in contact with the surface of the member 12 and will thus cause the threads-upo-n the" member15 to dig into the-'threadson-the bolt by amovementparallelto, the'jlongitudinal axis ofthe bolt and will also move inwardly so that a wedging action is maintained at all times between the member 15 and the bolt 10. The lower end '17 of the wedge member 15 is curved andhas a high projecting shoulder portion 17 which bites into the member 12-so as to securely hold the nut 13 against rotation, but making it easy when a wrench is applied to'the nut 13 to turn the nut backward andback it the bolt without the member l5 bitingsinto the member 12 so deeply as to prevent rotation of the nut 13 or destroy the surface I of the member 12 to such-an extent that the nut 13' cannot be readily placed in position.

7 I The member 15 is threaded with the same 7 size and standard threads as the threads'of forced inwardlytowards the center 'of the I bolt and the threads to bite into the threads of the bolt and at the'same time to slightly displace the threads upon the boltynot, how'- ever', to such an BXtGIllllLlliLl) the nut cannot be backed off the bolt. The nut is turned down fast upon the bolt and the shoulder portion 17? of the wedge member 15 is-thereupon caused to break into the-surfaceof the niemberl-Q tosuch an extent that the nut'l3 is held securelyin .pOsition and against any possibility of turning backwards ofi the bolt 10 and due to the elasticity of themetal any vibration will be taken up by the ac- '-tion of the wedge member 15. so that at no time will the nut' '13 beout ofgcontact orfloating, even for a small instant of time, and the nut 13 will therefore be held se-' curely'upon the bolt at all times and under all conditions of service, I 7

While I have described more or'less preciselythe details of construction, I do not wishto be. understood as limiting myself thereto, as I contemplate changes in form and the proportion of parts and the substitutions of equivalents, as circumstances may suggest or render expedient Without departing from the spirit or scope of'my invention.

1. In combination With a threaded bolt,

of a nut having a recess extending there through parallel with the longitudinal axis of the said nut andin communication with the nut opening, of a threaded Wedge shaped member in said recess extending beyond the inner end of said nut whereby Whenthe nut is turned down tightly the said wedge memher will be moved transversely of the said nut and inwardly towards the said bolt and into engagement withth'e side walls of the threadsof the said bolt.

2. In combination with athreadedbolt; v

of a nut havinga recess extending therethrough parallel with the bolt" opening and in communication therewith, the side walls of the said recess being parallel and the outside wall extending at an angle with respect to the longitudinal axis of the nut, of a wedge shaped threaded member located in'said recess and projecting beyond the inner face of said nut and in sliding engagement therewith, the outside edge of the said wedge member being parallel with the outside Wall of the said recess whereby as the nut is turned down thefwedge memberv is moved transversely of'the said bolt and in wardly-towards the said bolt and in inter locking engagement with the side walls'of the threads thereof;

Signed at Chicago; Illinois; this" 24th day of April, 1920. r

j ERIK-A, KWARNSTROM; 

